Some portable electronic devices may provide alert signals to a user indicating an incoming call, incoming text message, incoming short message service (SMS), upcoming appointments scheduled and noted in a calendar, alarm clocks, etc. Various types of alerts may be used to signal the user including, for example, a ringing sound and/or a mechanical vibration. A ringing sound or ringtone (e.g., a sequence of musical notes such as in a song or jingle, voices, sayings, or other audible sounds and noises) may use an electronic signaling device, such as a buzzer or loudspeaker, for example. In some cases, the ringing sound is provided in different cadences and with different loudness levels so that a user may select and fix a cadence and a sound intensity preferred by that user. The mechanical vibration using, for example, an electromechanical vibrator may be embedded in the portable electronic device. A vibrator mechanically vibrates the portable electronic device, communicating an alert signal and thus provides a relatively silent or less obtrusive alert signal as compared to the mechanical ring sound. Most users set the portable electronic device to the audible, ringing alert for most purposes, except where a meeting or similar event is occurring.
A disadvantage of manual selection between the ringing sound and mechanical vibration is that if a user forgets to manually disable the alert(s), an interruption caused by the ringing sound during an inopportune time such as, for example, during a meeting, during church services, and/or other public or private functions.
Another disadvantage is that the manual selection of a loudness or sound intensity by the user may fix the loudness or sound intensity for all environments, until the user manually changes the sound level. A selected (and fixed) sound level may be too low in a noisy environment and/or may be too high and intrusive in an intimate, low-key environment.